Jam/Jelly making

[gailforce1]

I have not made jam before and today picked 4lbs of blackberries. How much jam/jelly does 4lbs of fruit make? And I have no idea how many jars I need!
Thank you for any advice you can offer.

[justtheonethen]

My 1kg of blackberries made 6 jars of varying sizes so about 12?

[Mermaid36]

It will make less jelly as the actual fruit doesn't go into the end product :-)

[TondelayaDellaVentamiglia]

have you got a jam pan?

roughly you will need 1lb of sugar per pound of fruit, but you can reduce it a bit, say to three quarters per pound

If you do not want 8lbs or so of jam then if you go for jelly you get less

but for jelly you will need somewhere to strain the fruit over night, and a jelly bag.

[TondelayaDellaVentamiglia]

or make blackberry gin...I am going to try and do this when we ever see any brambles

[DustBunnyFarmer]

My top tips:

Depending on the weather, blackberries can be lower in pectin than in other fruit. If you are not using a specific jam sugar with added pectin, keep a couple of lemons handy and, if you are not getting a good set, add lemon juice to the simmering jam mixture. It should significantly improve the set of the jam. (Do you know about doing a 'wrinkle test'? Useful if you don't have a jam thermometer - low tech & very effective.)

Also, make sure you sterilise your jars well or you will end up with furry jam in a few months. I was told recently that it is usually contaminated lids that cause the problem when you are using old/recycling jars. I don't know how much truth there is to this.

I have also learned the hard way (don't ask!) that the little fruit fly maggots you sometimes get in blackberry jam do not mulch down and stay bright white in the finished jam. I gave up on blackberry jam and moved to straining the stewed berries through muslin or sieve to make jelly - guaranteed wriggler-free. If anyone has a foolproof way of coaxing the maggots out at the washing/preparation stage, though, I am all ears.

A ladle or jam collar (a wide necked funnel for filling jars) saves a lot of spattering/sticky mess - cooled jam is surprisingly difficult to remove from the outside of jars.

[DustBunnyFarmer]

That should have been fruit fly maggots in the berries, not the jam - but it's a moot point if you are going for full fruit jam.

[gailforce1]

Thank you all. We have so many blackberries I could probably pick another few pounds!

[DustBunnyFarmer]

On the pectin thing, cooking apples are good too - which is why they are often combined with blackberries in jam.

[justtheonethen]

I soak the blackberries in water with a pinch of salt. The little buggers come off then, you have to scoop the berries out rather than drain so you don't put them back on. Can't taste the salt in jam and if you don't swish you won't lose the taste/juice.

I use lemon juice and the pips tied in a muslin for pectin. The seeds have more apparently.

[justtheonethen]

Blackberry gin. Think I'll try that! How long do you leave it for? Sugar in too?

[Gymbunny1204]

I can gat you then amounts but try nigella' s jam recipe. I bake fruit and sugar in the oven, mix, voila - jam. Takes about half an hour. Delicious.

[justtheonethen]

Sounds v good method, will try that!

[BikeRunSki]

I like this recipe

[FishOn]

Yep when I was a kid we always soaked blackberries in salted water to kill the bugs.

[JamNan]

You should boil the lids to make sure they are sterile. Once you have cleaned the jars (dishwasher) put them in the oven on low to keep warm. You mustn't pour hot jam in cold jars as they are likely to crack. Put the lids on when the jam is hot or cold, never in between. Use waxed discs to keep airborne bacteria from the surface of the jam and fill to the top.

I would make jelly as I don't like the pips. Hugh F-W has
a nice bramble jelly recipe here

[PolkadotsAndMoonbeams]

I do boil the lids, but I put a cellophane covers under them too (as well as the waxed discs) - double whammy!

[Mermaid36]

To sterilise your jars, they should be in the oven for about 15 mins (at the least) at 115°C. I also put my lids in there as well.
I jar everything hot (jams, marmalades, chutneys and jellies)

[TondelayaDellaVentamiglia]

I dunno about quantities for the gin, for sloe gin I put a couple of inches of white sugar into the bottle, put in the sloes....at least three quarters full, top up with gin

keep it somewhere cool and shake it ever day until the sugar has dissolved and then a couple of times a week

let it sit for a couple of months (at least, longer won't hurt) and then strain it off, keep the fruit for adding to next year's jam

[RomComPhooey]

The recipe I used for damson vodka (based on a sloe gin one) was 1lb fruit, bottle of cheap vodka (750ml size) and 9-12oz sugar, to taste - i.e. 9oz for tarter finished product, 12oz for sweeter one.